Evaluation of interferon alpha-2B and thalidomide in patients with disseminated malignant melanoma, phase 2, SWOG 0026.

BACKGROUND

Southwest Oncology Group protocol 0026 evaluated interferon alpha-2b plus thalidomide in patients with disseminated melanoma. Endpoints were 6-month progression-free survival rate, response rate, and toxicity.

METHODS

Twenty-six patients with Stage IV melanoma, measurable or nonmeasurable disease, performance status of 0-2, and adequate renal and hepatic functions were registered. One prior systemic therapy for Stage IV disease was required. Interferon was administered subcutaneously (1 million U) twice daily; thalidomide was orally administered (200-400 mg) each evening in a dose-escalating manner. Response evaluations using Response Evaluation Criteria in Solid Tumors were performed every 8 weeks.

RESULTS

After 2 sudden deaths and 1 grade 4 treatment-related pulmonary embolism, this study was temporarily closed. One patient with deep-vein thrombosis and 2 with grade 3 cardiac arrhythmias were reported. The relationship of these events to the treatment was worrisome but not definitive. Grade 3 treatment-related adverse events occurred in 14 of 26 patients. Because of concern for patient safety the study was permanently closed. No treatment responses were seen in the 22 evaluable patients. Estimated 6-month progression-free survival rate was 15% (95% confidence interval [CI], 2%-29%), estimated 6-month overall survival was 58% (95% CI, 39%-77%), and estimated response probability was 0 of 22 (95% CI, 0%-15%).

CONCLUSIONS

This regimen demonstrated a lack of response and was associated with multiple severe toxicities. Further investigation of interferon alpha-2b and thalidomide in this dose and schedule is not warranted.